Aikins 2010.

Methods	Single‐centre RCT. University Hospital, Texas, USA
Participants	20 obese patients BMI > 27.5 kg/m2. Unclear whether patients undergoing surgery. Inclusion criteria: ASA II to III. Exclusion criteria: ASA IV to V Mean BMI (SD): FIS 32 (2.5); intubating SAD 34 (7); VLS 35 (4.5); stylet 34 (7) Mean age (SD): FIS 48.4 (16); intubating SAD 46.8 (9); VLS 40 (17); stylet 43 (14)
Interventions	Four intervention groups. Five participants randomly assigned to each of the following. FIS fibreoptic bronchoscope. 30 cc oral Bicitra (0.2 mg glycopyrrolate intravenously). Intubating SAD (Fastrach size 4 or 5) “Following insertion the cuff was inflated with 25‐40 ml of air and manual ventilation attempted. Tidal volumes >10 ml/kg, adequate movement of the chest wall and over 15 cm H2O airway pressure were judged acceptable ventilation. Only one attempt at blind intubation through the Fastrach™ with the silicone ett was undertaken. If unsuccessful, one attempt at fibreoptic bronchoscope guided tracheal intubation through the Fastrach™ was allowed” VLS (Bullard) Stylet (Trachlight)
Outcomes	Failed intubation. VLS, stylet and FIS: two attempts allowed with max time of 120 s Intubating SAD: one blind attempt, then one with FIS with max time 120 s Complications such as mucosal bleeding injury, hoarseness, dental injury, sore throat, difficult or painful swallowing assessed by participant review on POD0 and POD1 Time of insertion of test device into oropharynx to manual ventilation through TT
Details of anaesthetic induction and intubation	Rapid sequence induction Preoxygenation for three to five minutes; general anaesthesia was induced intravenously with 1 to 2 mg/kg propofol, 1 to 3 mcg/kg fentanyl and 1 mg/kg succinylcholine IV. After induction, cricoid pressure was maintained and mask ventilation verified. In all groups, an appropriately sized tracheal tube (TT) for oral intubation was chosen (inner diameter 7.5 to 8.0 mm in males and 7.0 to 7.5 mm in females) NBMA: 1 mg/kg succinylcholine
Training and seniority of intubator	Novice intubator (physician anaesthetist). Ten months' experience with direct laryngoscopy Viewed instructional videos and received didactic instruction on four devices. No more than five practical experience with devices
Notes	Statement indicating no sources of support and no conflicts of interest
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants randomly assigned—no further details
Allocation concealment (selection bias)	Unclear risk	No details
Blinding of participants and personnel (performance bias) Failed intubation, first success, ease of intubation and time for intubation	High risk	No mention of blinding
Blinding of participants and personnel (performance bias) Patient‐reported outcomes	Unclear risk	No details of how participants were treated after surgery and of pain relief, etc, given. Unclear whether recovery staff were blinded
Blinding of outcome assessment (detection bias) Failed intubation, first success, ease of intubation and time for intubation.	High risk	No mention of blinding
Blinding of outcome assessment (detection bias) Patient‐reported outcomes	Unclear risk	Not clear whether participant blinded. No standardized instruments described
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent loss to follow‐up
Selective reporting (reporting bias)	Low risk	All outcomes prespecified in Methods
Other bias	Low risk